Vehicle seats for motor vehicles, in particular the seats of the drivers or vehicle operators, can be provided with upholstered thigh supports. Thigh supports are generally understood as meaning a movable attachment in the front region to the seat surface on which the driver or vehicle occupant is sitting. Unlike the generally immovable seat surface, which is directly adjacent to the backrest, although the thigh support is provided with a resistance, it is nevertheless movable in its position with respect to the seat surface. For example, for a braking operation, the driver can therefore exert a downwardly directed force on the thigh supports with his/her thighs and can thus push the thigh support downward. The resistance which the thigh supports have in relation to the downward movement of the thighs may be balanced or set or determined in such a manner that the dead weight of the thighs or of the legs is provided with a comfortable support, but, on the other hand, during a conscious downward movement of the thighs, for example during a braking operation, the movement resistance of the thigh support does not cause any delay in the brake path.
It may be desirable to adapt the distance of the thigh support with respect to the seat surface and also the movement resistance in relation to conscious downward movements of the thighs, in particular during braking operations, to the anatomical circumstances of the driver.
The movement resistance in relation to a downwardly directed force, in particular a downward movement of the legs, is typically determined by the distance of the front wall of the thigh support from the seat surface and therefore from the available lever arm. A large distance between thigh support and seat surface generally signifies a large lever arm and therefore a small movement resistance of the thigh support, although people who set a far distance generally also require a large movement resistance in relation to downward movements so that the legs can comfortably rest on the thigh support during the journey. Conversely, a small distance between the front wall of the thigh support and seat surface generally signifies a small lever arm and therefore a large movement resistance of the thigh support, although people who set a small distance generally also only require a low movement resistance.
Seats having mechanisms which set the thigh supports by use of a forward and backward movement are known from the prior art. For example, U.S. Pat. No. 7,597,398 generally discloses the adaptation of a thigh support for different body heights. The thigh support here comprises a roller which is coupled to the seat frame and is adjustable relative to the seat frame between a retracted position and an extended position, wherein the seat cushion is at least partially wound around the roller while the roller is in the retracted position. By contrast, the seat cushion is at least partially unwound from the roller when the roller is in the extended position.
U.S. Pat. No. 7,192,087 generally discloses an adjustable thigh cushion system for vehicle seats. The system comprises an electric motor which provides a rotational movement for moving an upholstered slope forward and back.
U.S. Pat. No. 8,408,646 generally discloses a seat arrangement comprising a seat shell and a seat base, which seat arrangement is designed so as to additionally support the legs. In addition, the arrangement comprises a rod and a motor with a drive shaft which is connected to the rod in an operationally ready state and can rotate the rod, wherein the rotation of the drive shaft causes a displacement of the seat shell in a direction forward or rearward.
U.S. Pat. No. 9,399,418 likewise generally discloses a vehicle seat arrangement comprising a front seat surface with a supporting base which is adjustable between a raised and a lowered position by use of a motor. In addition, the arrangement has a second supporting base which is adjacent to the first supporting base and is activatable independently thereof. As a result, different supporting positions can be selected for the occupant's leg.
U.S. Pat. No. 6,578,915 generally describes the moving of the thigh support using a rod sliding mechanism for a chair. By use of the adjustable thigh support, the legs of the user can rest on a floor or can lie in a manner deposited in a relaxed sitting position on the thigh support. The thigh support interacts here with the backrest.
It would be desirable to provide for an improved adjustable or moveable thigh support for vehicle seats, in particular for motor vehicles.